'use strict';

const assert = require('assert');
const { createHash } = require('crypto');
const nconf = require('nconf');

const db = require('./mocks/databasemock');
const slugify = require('../src/slugify');
const utils = require('../src/utils');
const request = require('../src/request');

const install = require('../src/install');
const meta = require('../src/meta');
const user = require('../src/user');
const categories = require('../src/categories');
const topics = require('../src/topics');
const posts = require('../src/posts');
const privileges = require('../src/privileges');
const activitypub = require('../src/activitypub');

describe('ActivityPub integration', () => {
	before(async () => {
		meta.config.activitypubEnabled = 1;
		await install.giveWorldPrivileges();
	});

	after(() => {
		delete meta.config.activitypubEnabled;
	});

	describe('WebFinger endpoint', () => {
		let uid;
		let slug;
		const { host } = nconf.get('url_parsed');

		beforeEach(async () => {
			slug = slugify(utils.generateUUID().slice(0, 8));
			uid = await user.create({ username: slug });
		});

		it('should return a 404 Not Found if no user exists by that username', async () => {
			const { response } = await request.get(`${nconf.get('url')}/.well-known/webfinger?resource=acct:foobar@${host}`);

			assert(response);
			assert.strictEqual(response.statusCode, 404);
		});

		it('should return a 400 Bad Request if the request is malformed', async () => {
			const { response } = await request.get(`${nconf.get('url')}/.well-known/webfinger?resource=acct:foobar`);

			assert(response);
			assert.strictEqual(response.statusCode, 400);
		});

		it('should return 403 Forbidden if the calling user is not allowed to view the user list/profiles', async () => {
			await privileges.global.rescind(['groups:view:users'], 'guests');
			const { response } = await request.get(`${nconf.get('url')}/.well-known/webfinger?resource=acct:${slug}@${host}`);

			assert(response);
			assert.strictEqual(response.statusCode, 400);
			await privileges.global.give(['groups:view:users'], 'guests');
		});

		it('should return a valid WebFinger response otherwise', async () => {
			const { response, body } = await request.get(`${nconf.get('url')}/.well-known/webfinger?resource=acct:${slug}@${host}`);

			assert(response);
			assert.strictEqual(response.statusCode, 200);

			['subject', 'aliases', 'links'].forEach((prop) => {
				assert(body.hasOwnProperty(prop));
				assert(body[prop]);
			});

			assert.strictEqual(body.subject, `acct:${slug}@${host}`);

			assert(Array.isArray(body.aliases));
			assert([`${nconf.get('url')}/uid/${uid}`, `${nconf.get('url')}/user/${slug}`].every(url => body.aliases.includes(url)));

			assert(Array.isArray(body.links));
		});
	});

	describe('Helpers', () => {
		describe('.query()', () => {

		});

		describe('.generateKeys()', () => {

		});

		describe('.resolveId()', () => {
			let url;
			let resolved;

			before(() => {
				url = 'https://example.org/topic/foobar';
				resolved = 'https://example.org/tid/1234';
				activitypub._cache.set(`0;${url}`, {
					id: resolved,
				});
			});

			it('should return the resolved id when queried', async () => {
				const id = await activitypub.resolveId(0, url);
				assert.strictEqual(id, resolved);
			});

			it('should return null when the query fails', async () => {
				const id = await activitypub.resolveId(0, 'https://example.org/sdlknsdfnsd');
				assert.strictEqual(id, null);
			});

			it('should return null when the resolved host does not match the queried host', async () => {
				const url = 'https://example.com/topic/foobar'; // .com attempting to overwrite .org data
				const resolved = 'https://example.org/tid/1234'; // .org
				activitypub._cache.set(`0;${url}`, {
					id: resolved,
				});

				const id = await activitypub.resolveId(0, url);
				assert.strictEqual(id, null);
			});
		});

		describe('.resolveLocalId()', () => {
			let uid;
			let slug;

			beforeEach(async () => {
				slug = slugify(utils.generateUUID().slice(0, 8));
				uid = await user.create({ username: slug });
			});

			it('should return null when an invalid input is passed in', async () => {
				const { type, id } = await activitypub.helpers.resolveLocalId('ncl28h3qwhoiclwnevoinw3u');
				assert.strictEqual(type, null);
				assert.strictEqual(id, null);
			});

			it('should return null when valid input is passed but does not resolve', async () => {
				const { type, id } = await activitypub.helpers.resolveLocalId(`acct:foobar@${nconf.get('url_parsed').host}`);
				assert.strictEqual(type, 'user');
				assert.strictEqual(id, null);
			});

			it('should resolve to a local uid when given a webfinger-style string', async () => {
				const { id } = await activitypub.helpers.resolveLocalId(`acct:${slug}@${nconf.get('url_parsed').host}`);
				assert.strictEqual(id, uid);
			});

			it('should resolve even without the "acct:" prefix', async () => {
				const { id } = await activitypub.helpers.resolveLocalId(`${slug}@${nconf.get('url_parsed').host}`);
				assert.strictEqual(id, uid);
			});

			it('should resolve when passed a full URL', async () => {
				const { id } = await activitypub.helpers.resolveLocalId(`${nconf.get('url')}/user/${slug}`);
				assert.strictEqual(id, uid);
			});
		});
	});

	describe('ActivityPub screener middleware', () => {
		let uid;

		beforeEach(async () => {
			uid = await user.create({ username: slugify(utils.generateUUID().slice(0, 8)) });
		});

		it('should return regular user profile html if federation is disabled', async () => {
			delete meta.config.activitypubEnabled;

			const { response, body } = await request.get(`${nconf.get('url')}/uid/${uid}`, {
				headers: {
					Accept: 'text/html',
				},
			});

			assert(response);
			assert.strictEqual(response.statusCode, 200);
			assert(body.startsWith('<!DOCTYPE html>'));

			meta.config.activitypubEnabled = 1;
		});

		it('should return regular user profile html if Accept header is not ActivityPub-related', async () => {
			const { response, body } = await request.get(`${nconf.get('url')}/uid/${uid}`, {
				headers: {
					Accept: 'text/html',
				},
			});

			assert(response);
			assert.strictEqual(response.statusCode, 200);
			assert(body.startsWith('<!DOCTYPE html>'));
		});

		it('should return the ActivityPub Actor JSON-LD payload if the correct Accept header is provided', async () => {
			const { response, body } = await request.get(`${nconf.get('url')}/uid/${uid}`, {
				headers: {
					Accept: 'application/ld+json; profile="https://www.w3.org/ns/activitystreams"',
				},
			});

			assert(response);
			assert.strictEqual(response.statusCode, 200);
			assert(body.hasOwnProperty('@context'));
			assert(body['@context'].includes('https://www.w3.org/ns/activitystreams'));
		});
	});

	describe('User Actor endpoint', () => {
		let uid;
		let slug;

		beforeEach(async () => {
			slug = slugify(utils.generateUUID().slice(0, 8));
			uid = await user.create({ username: slug });
		});

		it('should return a valid ActivityPub Actor JSON-LD payload', async () => {
			const { response, body } = await request.get(`${nconf.get('url')}/uid/${uid}`, {
				headers: {
					Accept: 'application/ld+json; profile="https://www.w3.org/ns/activitystreams"',
				},
			});

			assert(response);
			assert.strictEqual(response.statusCode, 200);
			assert(body.hasOwnProperty('@context'));
			assert(body['@context'].includes('https://www.w3.org/ns/activitystreams'));

			['id', 'url', 'followers', 'following', 'inbox', 'outbox'].forEach((prop) => {
				assert(body.hasOwnProperty(prop));
				assert(body[prop]);
			});

			assert.strictEqual(body.id, `${nconf.get('url')}/uid/${uid}`);
			assert.strictEqual(body.type, 'Person');
		});

		it('should contain a `publicKey` property with a public key', async () => {
			const { response, body } = await request.get(`${nconf.get('url')}/uid/${uid}`, {
				headers: {
					Accept: 'application/ld+json; profile="https://www.w3.org/ns/activitystreams"',
				},
			});

			assert(body.hasOwnProperty('publicKey'));
			assert(['id', 'owner', 'publicKeyPem'].every(prop => body.publicKey.hasOwnProperty(prop)));
		});
	});

	describe('Instance Actor endpoint', () => {
		let response;
		let body;

		before(async () => {
			({ response, body } = await request.get(`${nconf.get('url')}/actor`, {
				headers: {
					Accept: 'application/ld+json; profile="https://www.w3.org/ns/activitystreams"',
				},
			}));
		});

		it('should respond properly', async () => {
			assert(response);
			assert.strictEqual(response.statusCode, 200);
		});

		it('should return a valid ActivityPub Actor JSON-LD payload', async () => {
			assert(body.hasOwnProperty('@context'));
			assert(body['@context'].includes('https://www.w3.org/ns/activitystreams'));

			['id', 'url', 'inbox', 'outbox', 'name', 'preferredUsername'].forEach((prop) => {
				assert(body.hasOwnProperty(prop));
				assert(body[prop]);
			});

			assert.strictEqual(body.id, body.url);
			assert.strictEqual(body.type, 'Application');
			assert.strictEqual(body.name, meta.config.site_title || 'NodeBB');
			assert.strictEqual(body.preferredUsername, nconf.get('url_parsed').hostname);
		});

		it('should contain a `publicKey` property with a public key', async () => {
			assert(body.hasOwnProperty('publicKey'));
			assert(['id', 'owner', 'publicKeyPem'].every(prop => body.publicKey.hasOwnProperty(prop)));
		});

		it('should also have a valid WebFinger response tied to `preferredUsername`', async () => {
			const { response, body: body2 } = await request.get(`${nconf.get('url')}/.well-known/webfinger?resource=acct:${body.preferredUsername}@${nconf.get('url_parsed').host}`);

			assert.strictEqual(response.statusCode, 200);
			assert(body2 && body2.aliases && body2.links);
			assert(body2.aliases.includes(nconf.get('url')));
			assert(body2.links.some(item => item.rel === 'self' && item.type === 'application/activity+json' && item.href === `${nconf.get('url')}/actor`));
		});
	});

	describe('http signature signing and verification', () => {
		describe('.sign()', () => {
			let uid;

			before(async () => {
				uid = await user.create({ username: utils.generateUUID().slice(0, 10) });
			});

			it('should create a key-pair for a user if the user does not have one already', async () => {
				const endpoint = `${nconf.get('url')}/uid/${uid}/inbox`;
				const keyData = await activitypub.getPrivateKey('uid', uid);
				await activitypub.sign(keyData, endpoint);
				const { publicKey, privateKey } = await db.getObject(`uid:${uid}:keys`);

				assert(publicKey);
				assert(privateKey);
			});

			it('should return an object with date, a null digest, and signature, if no payload is passed in', async () => {
				const endpoint = `${nconf.get('url')}/uid/${uid}/inbox`;
				const keyData = await activitypub.getPrivateKey('uid', uid);
				const { date, digest, signature } = await activitypub.sign(keyData, endpoint);
				const dateObj = new Date(date);

				assert(signature);
				assert(dateObj);
				assert.strictEqual(digest, null);
			});

			it('should also return a digest hash if payload is passed in', async () => {
				const endpoint = `${nconf.get('url')}/uid/${uid}/inbox`;
				const payload = { foo: 'bar' };
				const keyData = await activitypub.getPrivateKey('uid', uid);
				const { digest } = await activitypub.sign(keyData, endpoint, payload);
				const hash = createHash('sha256');
				hash.update(JSON.stringify(payload));
				const checksum = hash.digest('base64');

				assert(digest);
				assert.strictEqual(digest, `sha-256=${checksum}`);
			});

			it('should create a key for NodeBB itself if a uid of 0 is passed in', async () => {
				const endpoint = `${nconf.get('url')}/uid/${uid}/inbox`;
				const keyData = await activitypub.getPrivateKey('uid', 0);
				await activitypub.sign(keyData, endpoint);
				const { publicKey, privateKey } = await db.getObject(`uid:0:keys`);

				assert(publicKey);
				assert(privateKey);
			});

			it('should return headers with an appropriate key id uri', async () => {
				const endpoint = `${nconf.get('url')}/uid/${uid}/inbox`;
				const keyData = await activitypub.getPrivateKey('uid', uid);
				const { signature } = await activitypub.sign(keyData, endpoint);
				const [keyId] = signature.split(',');

				assert(signature);
				assert.strictEqual(keyId, `keyId="${nconf.get('url')}/uid/${uid}#key"`);
			});

			it('should return the instance key id when uid is 0', async () => {
				const endpoint = `${nconf.get('url')}/uid/${uid}/inbox`;
				const keyData = await activitypub.getPrivateKey('uid', 0);
				const { signature } = await activitypub.sign(keyData, endpoint);
				const [keyId] = signature.split(',');

				assert(signature);
				assert.strictEqual(keyId, `keyId="${nconf.get('url')}/actor#key"`);
			});
		});

		describe('.verify()', () => {
			let uid;
			let username;
			const baseUrl = nconf.get('relative_path');
			const mockReqBase = {
				method: 'GET',
				// path: ...
				baseUrl,
				headers: {
					// host: ...
					// date: ...
					// signature: ...
					// digest: ...
				},
			};

			before(async () => {
				username = utils.generateUUID().slice(0, 10);
				uid = await user.create({ username });
			});

			it('should return true when the proper signature and relevant headers are passed in', async () => {
				const endpoint = `${nconf.get('url')}/user/${username}/inbox`;
				const path = `/user/${username}/inbox`;
				const keyData = await activitypub.getPrivateKey('uid', uid);
				const signature = await activitypub.sign(keyData, endpoint);
				const { host } = nconf.get('url_parsed');
				const req = {
					...mockReqBase,
					...{
						path,
						headers: { ...signature, host },
					},
				};

				const verified = await activitypub.verify(req);
				assert.strictEqual(verified, true);
			});

			it('should return true when a digest is also passed in', async () => {
				const endpoint = `${nconf.get('url')}/user/${username}/inbox`;
				const path = `/user/${username}/inbox`;
				const keyData = await activitypub.getPrivateKey('uid', uid);
				const signature = await activitypub.sign(keyData, endpoint, { foo: 'bar' });
				const { host } = nconf.get('url_parsed');
				const req = {
					...mockReqBase,
					...{
						method: 'POST',
						path,
						headers: { ...signature, host },
					},
				};

				const verified = await activitypub.verify(req);
				assert.strictEqual(verified, true);
			});
		});
	});

	describe('Receipt of ActivityPub events to inboxes (federating IN)', () => {
		describe('Create', () => {
			describe('Note', () => {
				const slug = utils.generateUUID();
				const id = `https://example.org/status/${slug}`;
				const remoteNote = {
					'@context': 'https://www.w3.org/ns/activitystreams',
					id,
					url: id,
					type: 'Note',
					to: ['https://www.w3.org/ns/activitystreams#Public'],
					cc: ['https://example.org/user/foobar/followers'],
					inReplyTo: null,
					attributedTo: 'https://example.org/user/foobar',
					name: 'Foo Bar',
					content: '<b>Baz quux</b>',
					published: new Date().toISOString(),
					source: {
						content: '**Baz quux**',
						mediaType: 'text/markdown',
					},
				};
				const remoteUser = {
					'@context': 'https://www.w3.org/ns/activitystreams',
					id: 'https://example.org/user/foobar',
					url: 'https://example.org/user/foobar',

					type: 'Person',
					name: 'Foo Bar',
					preferredUsername: 'foobar',
					publicKey: {
						id: 'https://example.org/user/foobar#key',
						owner: 'https://example.org/user/foobar',
						publicKeyPem: 'publickey',
					},
				};

				let topic;

				before(async () => {
					const controllers = require('../src/controllers');

					activitypub._cache.set(`0;${id}`, remoteNote);
					activitypub._cache.set(`0;https://example.org/user/foobar`, remoteUser);
					await db.sortedSetAdd(`followersRemote:${remoteUser.id}`, Date.now(), 1); // fake a follow
					await controllers.activitypub.postInbox({
						body: {
							type: 'Create',
							actor: 'https://example.org/user/foobar',
							object: remoteNote,
						},
					}, { sendStatus: () => {} });
				});

				it('should create a new topic if Note is at root-level or its parent has not been seen before', async () => {
					const saved = await db.getObject(`post:${id}`);

					assert(saved);
					assert(saved.tid);

					topic = await topics.getTopicData(saved.tid);
					assert(topic);
					assert.strictEqual(saved.uid, 'https://example.org/user/foobar');
					assert.strictEqual(saved.content, '<b>Baz quux</b>');
				});

				it('should properly save the topic title in the topic hash', async () => {
					assert.strictEqual(topic.title, 'Foo Bar');
				});

				it('should properly save the mainPid in the topic hash', async () => {
					assert.strictEqual(topic.mainPid, id);
				});

				// todo: test topic replies, too
			});
		});
	});

	describe('Serving of local assets to remote clients', () => {
		let category;
		let uid;
		let postData;
		let topicData;

		before(async () => {
			category = await categories.create({ name: utils.generateUUID().slice(0, 8) });
			const slug = slugify(utils.generateUUID().slice(0, 8));
			uid = await user.create({ username: slug });

			({ postData, topicData } = await topics.post({
				uid,
				cid: category.cid,
				title: 'Lipsum title',
				content: 'Lorem ipsum dolor sit amet',
			}));
		});

		describe('Note', () => {
			let body;
			let response;

			before(async () => {
				({ body, response } = await request.get(`${nconf.get('url')}/post/${postData.pid}`, {
					headers: {
						Accept: 'application/ld+json; profile="https://www.w3.org/ns/activitystreams"',
					},
				}));
			});

			it('should return a 404 on a non-existant post', async () => {
				const { response } = await request.get(`${nconf.get('url')}/post/${parseInt(postData.pid, 10) + 1}`, {
					headers: {
						Accept: 'application/ld+json; profile="https://www.w3.org/ns/activitystreams"',
					},
				});

				assert.strictEqual(response.statusCode, 404);
			});

			it('should return a 200 response on an existing post', () => {
				assert.strictEqual(response.statusCode, 200);
			});

			it('should return the expected Content-Type header', () => {
				assert.strictEqual(response.headers['content-type'], 'application/activity+json; charset=utf-8');
			});
		});
	});

	describe('Actor asserton', () => {
		describe('happy path', () => {
			let uid;
			let actorUri;

			before(async () => {
				uid = utils.generateUUID().slice(0, 8);
				actorUri = `https://example.org/user/${uid}`;
				activitypub._cache.set(`0;${actorUri}`, {
					'@context': 'https://www.w3.org/ns/activitystreams',
					id: actorUri,
					url: actorUri,

					type: 'Person',
					name: 'example',
					preferredUsername: 'example',

					publicKey: {
						id: `${actorUri}#key`,
						owner: actorUri,
						publicKeyPem: 'somekey',
					},
				});
			});

			it('should return true if successfully asserted', async () => {
				const result = await activitypub.actors.assert([actorUri]);
				assert(result);
			});

			it('should contain a representation of that remote user in the database', async () => {
				const exists = await db.exists(`userRemote:${actorUri}`);
				assert(exists);

				const userData = await user.getUserData(actorUri);
				assert(userData);
				assert.strictEqual(userData.uid, actorUri);
			});

			it('should save the actor\'s publicly accessible URL in the hash as well', async () => {
				const url = await user.getUserField(actorUri, 'url');
				assert.strictEqual(url, actorUri);
			});
		});

		describe('edge case: loopback handles and uris', () => {
			let uid;
			const userslug = utils.generateUUID().slice(0, 8);
			before(async () => {
				uid = await user.create({ username: userslug });
			});

			it('should return true but not actually assert the handle into the database', async () => {
				const handle = `${userslug}@${nconf.get('url_parsed').host}`;
				const result = await activitypub.actors.assert([handle]);
				assert(result);

				const handleExists = await db.isObjectField('handle:uid', handle);
				assert.strictEqual(handleExists, false);

				const userRemoteHashExists = await db.exists(`userRemote:${nconf.get('url')}/uid/${uid}`);
				assert.strictEqual(userRemoteHashExists, false);
			});

			it('should return true but not actually assert the uri into the database', async () => {
				const uri = `${nconf.get('url')}/uid/${uid}`;
				const result = await activitypub.actors.assert([uri]);
				assert(result);

				const userRemoteHashExists = await db.exists(`userRemote:${uri}`);
				assert.strictEqual(userRemoteHashExists, false);
			});
		});
	});
});